Embryonic
stem cell (ESC) research is at the frontier of modern medicine.
It offers the potential for lifesaving new treatments, possibly
cures, for devastating diseases and at the same time challenges
us to consider difficult questions about the earliest stages of
human life and what kind of limits should be imposed on research
in pursuit of medical advances.

There
is no question that embryonic stem cells have enormous potential
to ease suffering and save lives. They have the ability to generate
virtually any kind of tissue as well as coordinate repair processes
within the body. If we can determine how these cells function
and how to guide their production of functional cells, the potential
benefits are almost unimaginable. On the other hand, these cells
are found only in the earliest stages of human development, and
generation of new lines of cells, using current technology, requires
the destruction of a human embryo.
Opponents of all research on human
embryonic stem cells consider the blastocyst, the early-stage
embryo from which these undifferentiated cells are derived, to
be a human life and object to its destruction.
However, most blastocyst sources
of embryonic stem cells are from in vitro fertilization (IVF)
clinics, where embryos that have not been implanted are routinely
destroyed or indefinitely frozen. A survey of couples with embryos
frozen for more than two years showed that 44% preferred indefinite
storage of embryos, 21% opted for donation to research, and 34%
preferred that their embryos be discarded. These data highlight
the wide range of public opinion regarding the ethical boundaries
in use of human embryos in research.
In an attempt to address conflicting
priorities and opinions surrounding this research, President Bush
placed tight restrictions on federally funded ESC work in 2001,
limiting scientists who receive federal money to work only with
an established set of 64 cell lines. The federally approved cell
lines were all obtained from embryos left over from IVF procedures
prior to August 4, 2001, the date of the new policy’s implementation.
Federal money cannot be used for projects that involve derivation
of new stem cell lines, even from embryos that would otherwise
be destroyed.
However, the new policy does not
restrict privately funded work, and studies involving the derivation
of new stem cell lines, and use of those cells for many different
types of research, continue in many areas of the United States
and internationally.
In California, a groundswell of
public support led to passage of Proposition 71, a remarkable
measure allocating $3 billion in state money for research using
new human ESC lines. Other U.S. institutions have used private
money and facilities to derive new lines, and many states are
considering measures similar to California’s, which allows
scientists to work outside the federal restrictions.
Meanwhile, scientists working in
institutions that receive federal grants are left with older,
suboptimal ESC lines. Since the president’s announcement,
it has become clear that many of the 64 “established”
lines are not really established at all. Many are simply not viable,
and others will not grow in the lab. For example, the six lines
derived at Sweden’s Karolinska Institute all failed to expand
in culture and cannot be used. Other approved lines sustained
chromosomal damage during their cultivation, meaning that they
are not true copies of the original stem cells and are basically
tumors. These cells continue to divide but their growth may be
uncontrollable, and their tumor-like behavior precludes use in
a clinical setting.

In
the midst of this turbulent situation, Emory and Georgia Tech have
agreed to support a core facility for human embryonic stem cell
cultivation. The goal of this facility is to provide researchers
on both campuses with high-quality cells as they explore new treatments.
We made the decision to use only lines
approved by the federal government for federally funded work to
avoid jeopardizing the federal funding of our colleagues. Nonetheless,
we recognize that the approved lines are clearly unsuited for many
applications, and the decision to use them is a compromise to balance
science with political constraints. Furthermore, the initial research
in the core will be directed at methods to prevent chromosomal mutations
in the cell lines and maximize their utility for ongoing studies.
As a society, we must address the
complex ethical dilemmas posed by stem cell technologies. Despite
the 2001 decision, scientists funded outside the NIH continue to
make progress with new lines, forging a path toward application
of the cells in the clinic.
Even if we make the existing federally
approved lines viable for some research applications, they are not
now and never
will be suitable for transplantation into patients. New lines will
be needed. Sooner or later, institutional review boards that oversee
any new experimental treatments in humans will be forced to weigh
the individual and societal benefit of stem cell research and therapy
versus its risks, both medical and ethical.
Some regulation of the process of
derivation, cultivation, and use of human embryonic stem cells is
certainly warranted. Well-accepted regulations covering patient
privacy and the safety of clinical research protocols serve as a
basis for developing similar standards to regulate the appropriate
derivation and use of these cells. As recommended by the National
Academy of Sciences, the Emory/Georgia Tech core facility will be
overseen by an advisory board.
In my opinion, current restrictions
should be replaced by enforceable standards for both the precise
sources of embryos to be used and the circumstances under which
obtaining them would be permissible. The standards would include
specific limits on which embryos could be used. For example, those
that could conceivably be implanted should not be used. The rules
must also specify strict privacy for donors and their genetic information
and establish a clear consent process for donation of embryos for
this research.
Proponents of deriving new stem cell
lines suggest that blastocysts—particularly those created
outside a woman’s body for the purpose of assisted reproduction—are
equivalent to brain dead donors of solid organs.
Federally established standards regulating
organ donation have served the transplant community well and are
a credible model for an embryo donation consent process.
Though united by a desire for advancing
the common welfare, good people continue to disagree over this issue.
As scientists, we should make the dialogue over ethical practices
a constant part of our ongoing decision-making, both within our
institution and at the level of the broader science
community.
Here at Emory and at Georgia Tech,
we are committed to supporting the best research possible within
the existing legal framework. By improving the capabilities of the
existing cell lines, we aim to help publicly funded research in
this area reach its fullest potential. At the same time, we must
participate in the larger public dialogue over the direction of
stem cell research, to ensure that its great potential is realized.

Marie
Csete is assistant professor of cell biology and the John E. Steinhaus
Professor of Anesthesiology in the School of Medicine.